This application is based on Patent Application No. 9-349,701 (1997) filed Dec. 18, 1997 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates generally to an ink-jet printing apparatus and an ink-jet printing method. More particularly, the invention relates to an ink-jet printing apparatus and an ink-jet printing method performing printing using inks adapted to printing media to be used for printing.
2. Description of the Related Art
As a printing method to obtain high definition and high preciseness image, a printing method employing an ink-jet printing apparatus performing ink ejection using a thermal energy generated by an electrothermal transducer, has been known. The ink-jet printing apparatus of this system has less constraint in selection of the printing media actually used in the light of principle of printing. In the recent years, kinds of printing media to be used in such printing apparatus is becoming wide variety. By the ink-jet printing apparatus, in addition to a coated paper which has been used conventionally, printing can be performed on plain paper, what we call, transparent sheet, glossy paper, a back-print film, leather, wood or the like, for example. In the alternative, textile printing can also be performed on a cloth fabricated from cotton, rayon (artificial silk), hemp, silk, nylon, polyester or the like.
On the other hand, associating with increasing the variety of printing media to be used, in viewpoint of use of inks adapted to property of the printing media, such as material or the like, kinds of inks to be used in the ink-jet printing apparatus is increasing. As such inks, in addition to a water soluble dye ink which has been used normally, a water-soluble dye ink in concentrated form, an ink using a water insoluble dye, a pigment ink, a non-aqueous ink and the like are used, for example.
These large number of kinds of inks are used depending upon kind of the printing media, color or density required in printing images, image fastness and so on, namely depending upon specification required for printing apparatus. Therefore, the large number of kinds of inks are used by simultaneously using several kinds of inks in the same printing apparatus, or by exchanging inks within a printing head or an ink path every time of varying kinds of the printing media.
However, among large number of kinds of inks just described, when a water-soluble dye ink in concentrated form, an ink using water insoluble dye, a pigment ink and the like are used, for example, it is relatively difficult to stably eject the ink from the printing head to possibly cause plugging or ejection failure, and damaging of the head caused by plugging or ejection failure.
Particularly, in the ink-jet printing apparatus using a thermal energy by the electrothermal transducer, damage, to which the printing head is subjected by the heat, degree of bubbling, variation of viscosity of the ink, initial ejection characteristics and so on have varied depending upon the kind of the ink to be used. Therefore, difficulty is encountered to perform optimal ejection for all kinds of the inks under the same head driving condition.
The present invention has been worked out in view of resolving the problems set forth above. Therefore, it is an object of the present invention to provide an ink-jet printing apparatus and an in-jet printing method which may not cause problem in ejection characteristics and life of a printing head even when a plurality of kinds of inks having different characteristics are used.
In a first aspect of the present invention, there is provided an ink-jet printing apparatus performing printing on a printing medium by a printing head using a plurality of kinds of inks and ejecting the ink utilizing thermal energy, comprising:
ink discriminating means discriminating kind of the ink on the basis of information relating to kind of the ink ejected from the printing head;
driving condition setting means for setting a driving condition of the printing head on the basis of the kind of ink discriminated by the ink discriminating means; and
head driving control means for controlling driving of the printing head for ejection on the basis of the driving condition set by the driving condition setting means.
Here, the driving condition of the printing head may be a condition relating to a generation amount of a thermal energy.
Information in relation to kind of the ink may be kind of the ink or kind of the printing medium.
The printing head may generate the thermal energy by application of a divided pulse consisted of a plurality of pulses and the driving condition setting means may set a pulse width of a leading pulse depending upon the discriminated kind of the ink.
The drive condition setting means may set a pulse width of the trailing pulse constant irrespective of kind of the discriminated kind of the ink.
The driving condition setting means may consist the divided pulse for ejection opening of the printing head not ejecting the ink with only leading pulse, and applied amount of the leading pulse may be controlled depending upon the discriminated kind of the ink.
At least one kind of the plurality of kinds of inks may be a water insoluble ink or a pigment ink.
The printing medium may be a cloth.
At least a combination of the printing medium being a polyester cloth and the ink being a disperse dye ink, may be included.
A plurality of kinds of inks may be a dye ink and a pigment ink, respectively.
A plurality of kinds of inks may be reactive dye ink and a disperse dye ink.
When printing is performed on the printing medium by the printing head ejecting the disperse dye ink, the driving condition setting means may set the pulse width of the leading pulse small.
In a second aspect of the present invention, there is provided an ink-jet printing method comprising:
first step of discriminating a kind of an ink on the basis of an information concerning a kind of the ink to be ejected from a printing head ejecting the ink utilizing a thermal energy using a plurality of kinds of inks,
second step of setting a driving condition of the printing head on the basis of the kind of the ink discriminated at the first step; and
third step of controlling driving of the printing head for ejection on the basis of the driving condition set at the second step.
Here, the driving condition of the printing head may be a condition relating to a generation amount of a thermal energy.
Information in relation to kind of the ink may be kind of the ink or kind of the printing medium.
The printing head may generate the thermal energy by application of a divided pulse consisted of a plurality of pulses and a pulse width of a leading pulse depending upon the discriminated kind of the ink is set.
A pulse width of the trailing pulse constant irrespective of kind of the discriminated kind of the ink may be set.
The divided pulse for ejection opening of the printing head not ejecting the ink with only leading pulse may be set, and applied amount of the leading pulse controlled depending upon the discriminated kind of the ink may be set.
At least one kind of the plurality of kinds of inks may be a water insoluble ink or a pigment ink.
The printing medium may be a cloth.
At least a combination of the printing medium being a polyester cloth and the ink being a disperse dye ink, may be included.
A plurality of kinds of inks may be a dye ink and a pigment ink, respectively.
A plurality of kinds of inks may be reactive dye ink and a disperse dye ink.
When printing is performed on the printing medium by the printing head ejecting the disperse dye ink, the pulse width of the leading pulse small may be set.
With the construction set forth above, in the ink-jet printing apparatus which can use a plurality of kinds of inks, a kind of the ink to be used for printing is discriminated. Depending upon this, head driving condition relating to generation amount of the thermal energy in the head relating to the ink ejection, is set. Therefore, irrespective of the kind of the ink to be used, ejection characteristics can be constantly optimal. Also, damage for the head upon ejection can be minimized.
As set forth above, according to the present invention, in the ink-jet printing apparatus capable of using a plurality of kinds of the inks, the kind of the ink to be used for printing can be discriminated. Depending upon result of discrimination, a head driving condition relating to generation amount of the thermal energy in the head relating to ink ejection, can be set to constantly optimize ejection characteristics irrespective of the kind of the ink to be used. Also, damage of the head upon ejection can be minimized.
As a result, it becomes possible to provide the ink-jet printing apparatus which can avoid plugging of the ink or ejection failure, prevent occurrence of damaging of the head and so on, and stably output high definition and high preciseness image on each kind of the printing medium.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of the embodiments thereof taken in conjunction with the accompanying drawings.